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1G horrible gas mileage/end clutch issue

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enriquez2000

Proven Member
2,277
820
Oct 5, 2014
fort collins, Colorado
Might be seperate or combined issue but im stock and average 14 to 15mpg in my awd auto turbo 1g. I sometimea lose OD/4th gear. O2 sensor cel comes and goes as well but looks like last owner replaced it. Have a new one im putting in shortly.

I saw the loss of 4th is common and looks easily serviceable, so that kits on the way. Rest of gears are great.

What else could be my issues? Cracked manny or 02 pipe? I should at least be getting 18 or more i would think.
 
Autos and 4cyl motors aren't made for each other-period.

That heavy tranny with the complex gear system inside eats up the power from a small motor moving a hefty chassis and alone spinning another drive shaft to move the rear wheels..That's a lot of work with all of them axles demanding power.

But, with the OD thing acting up, you're running in third which is causing higher RPMS and reducing mileage real bad - it's like being in third gear for a manual all the time instead of using fourth gear.

Get the tranny fixed, then see what the MPG numbers looks like.
 
Autos and 4cyl motors aren't made for each other-period.

That heavy tranny with the complex gear system inside eats up the power from a small motor moving a hefty chassis and alone spinning another drive shaft to move the rear wheels..That's a lot of work with all of them axles demanding power.

But, with the OD thing acting up, you're running in third which is causing higher RPMS and reducing mileage real bad - it's like being in third gear for a manual all the time instead of using fourth gear.

Get the tranny fixed, then see what the MPG numbers looks like.
Thanks. Parts are ordered and looks simple enough to do. Also looks like it was designed to be serviceable since it drops out with 4 bolts. Just crazy how low the mileage is. My 6cyl grandprix gets 24mpg
 
how good is it running?

other than the 02 randomly going on or off at no particular time or reason and cruising the highway at 5k RPMs it runs exceptionally well... Has 138k miles on it and immediately did all tune up stuff when I got it. I got this thing cheap because the guy before me put a N/A tpu in it because the old one crapped out.. I didnt notice the OD issue until I drove it to work, it does great shifting in the city
 
id start by checking for boost leaks. i could see that hurting your mpgs. also check tire pressure
wouldnt boost leaks cause crappy performance? I have a 600+ hp Honda accord and when there was boost leaks it sputtered like mad!

I have a 2g mani and 02 dump on the way.. I did read the 1g is prone to having cracks..
 
Yeah I'd do tranny and diff fluid and see if that helps

ok.. ya it smells clean and looks clean but who knows.. after the end kit goes in all fluids will be fresh.. until then i just have to fill up every day HAHAHA[DOUBLEPOST=1413904127][/DOUBLEPOST]on another note.. what size are all the bolts for the turbo and the 02 housing? I have all 2g stuff coming in to swap and wanted to get the proper hardware so its all fresh
 
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Well this might mean something....
well looks like that picture didnt work but its my emission report.. my CO is 187... so dumping way too much fuel
 
You running a T-stat? If not, the system's coolant sensor is telling the ECU to pour more fuel in to get the block heated up, which will cause a rich mixture.

A low setting T-stat will do about the same thing. Our systems love hot 196* T-stats for prime operations.
 
You running a T-stat? If not, the system's coolant sensor is telling the ECU to pour more fuel in to get the block heated up, which will cause a rich mixture.

A low setting T-stat will do about the same thing. Our systems love hot 196* T-stats for prime operations.
Yes i have a thermostat in.. but ill look into a new one... also, no codes but thinking about replacing coolant temp sensor too
 
I noticed that no one ever goes back and puts solutions in these things, but I found my gas mileage issue.

In my case the previous owner put a N/T ecu in the car. so My ecu was telling the car to dump fuel like it had 240cc injectors and not the 390 that mine actually has. so basically at 50% duty my car was dumping 62% more fuel than it should be.
 
I noticed that no one ever goes back and puts solutions in these things, but I found my gas mileage issue.

In my case the previous owner put a N/T ecu in the car. so My ecu was telling the car to dump fuel like it had 240cc injectors and not the 390 that mine actually has. so basically at 50% duty my car was dumping 62% more fuel than it should be.

i have the same issue except backwards im running 390 cc injectos with nt ecu , resister pack , my cars a turbo swap to non turbo i have the 240cc injectors sitting in my car waiting to get instaled aswell as the fpr so that means i would also be running rich? buying a delete plug soon so i can turbo next spring but for now my gas milage is beyound terrible

oh and make sure the person put in the right fuel pressure reg
 
I doubt it was touched.. nothing else was... it was an unmolested motor. Old man just didnt know what tcu and ecu to use apparently.
 
i have the same issue except backwards im running 390 cc injectos with nt ecu , resister pack , my cars a turbo swap to non turbo i have the 240cc injectors sitting in my car waiting to get instaled aswell as the fpr so that means i would also be running rich? buying a delete plug soon so i can turbo next spring but for now my gas milage is beyound terrible

oh and make sure the person put in the right fuel pressure reg
yes with 390cc injectors you are running about 60% more fuel than you should be.
 
I doubt it was touched.. nothing else was... it was an unmolested motor. Old man just didnt know what tcu and ecu to use apparently.
yea your best bet is to use the right tcu prob why your loseing over drive ,,,

and really yeah i gotta get that plug in the mail! so technacly my fuel efficiency will increase 60% when i swap?
 
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